Merged commit includes the following changes: (#10058)

378492389  by Andre Araujo:

    Internal change

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369671840  by Andre Araujo:

    Cleanup after recent PRs in DELF github repo.

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360692342  by Andre Araujo:

    Replace direct TF app import with absl::app.
    (1) TF::app is deprecated
    (2) direct TF import is discouraged. go/gpylint-faq#g-direct-tensorflow-import

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359157762  by Andre Araujo:

    Internal change

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PiperOrigin-RevId: 378492389
Co-authored-by: Andre Araujo <andrearaujo@google.com>

research/delf/delf/python/training/model/delg_model_test.py

@@ -37,7 +37,7 @@ class DelgTest(tf.test.TestCase, parameterized.TestCase):
     batch_size = 2
     input_shape = (batch_size, image_size, image_size, 3)
     local_feature_dim = 64
-    feature_map_size = image_size // 16 # reduction factor for resnet50.
+    feature_map_size = image_size // 16  # reduction factor for resnet50.
     if block3_strides:
       feature_map_size //= 2